Contained herein is material, including material incorporated by reference, which is subject to copyright protection. The copyright owner does not object to the electronic, facsimile or electro-photographic reproduction of the patent disclosure by any person as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all rights to the copyright whatsoever.
The invention relates to printers and other hard copy output engines. More particularly, the invention relates to estimation of usage for a hard copy output engine and relating estimated usage to need for consumables.
As computer systems and data communications systems have developed, the number and variety of hard copy output engines employed in a typical office or factory setting has grown. Examples include photo copiers, facsimile machines, printers and devices including more than one of these capabilities.
Additionally, increased sophistication of hard copy output engines has increased both the number and variety of consumables associated with the hard copy output engines. For example, color laser printers typically employ a plurality of toner cartridges. Some color laser printers employ at least four or more different toner cartridges. An example of such a system is described in U.S. Pat. No. 5,796,422, entitled xe2x80x9cDirect Toner Projection Printing Using An Intermediate Transfer Mediumxe2x80x9d, issued to G. Hanson et al., which is assigned to the assignee of this patent document and which is hereby incorporated herein for its teachings. Examples of laser printers using multiple toner cartridges include Models 4500, 4550, 8500 and 8550 available from the Hewlett-Packard Company of Palo Alto, Calif. One arrangement that has been employed provides separate black, cyan, magenta and yellow toner cartridges. As a result, the need to replace toner cartridges increases. Similar situations arise in conjunction with other types of printers using other types of pigmentation material, such as ink jet printers and printers employing pigmentation technologies based on phase changes.
Further, the operating parameters relevant to placement of controlled amounts of toner to achieve specific shades can be variable. Factors influencing these parameters include atmospheric humidity, ageing of components, amount of toner in the cartridge and the like. As a result, some form of feedback is highly desirable for maintaining color integrity as well as print density.
One manner in which this feedback can be supplied is to print a standard pattern periodically and to compare measurements made on the standard pattern to expected measurement values. When this process is used in a color laser printer, it may be employed at regular intervals, such as every four hours, and may take several minutes. It is generally undesirable to have this self-calibration exercise occur during a period of peak usage.
Additionally, it is generally desirable to try to anticipate when a consumable supply, such as one of the toner cartridges, may run out. Coordination of orders for supplies can be very helpful to avoid over- or under-stocking of these consumable commodities, while still achieving the benefits of economies of scale by pooling orders to service multiple hard copy output engines, especially those using at least some of the same consumable commodities. However, in many business settings, the sheer number of diverse hard copy output engines being used in different aspects or divisions of the business may lead to confusion in maintaining adequate supplies of these consumable commodities.
What is needed is a way to try to anticipate need for service events such as consumable replacement or self calibration in a manner that attempts to avoid interruption of peak usage periods.
In accordance with an aspect of the present invention, a method of scheduling service events for a hard copy output engine includes estimating when a service event is likely to occur and estimating, from a record of past usage, when peak usage is likely to occur. The method also includes determining when the service event estimate is contemporaneous with the peak usage estimate and executing a predetermined protocol when determining is indicative of contemporaneous estimates.
In accordance with another aspect of the present invention, a method of scheduling service events for a hard copy output engine includes estimating, using a record of past usage of the hard copy output engine, when a service event is likely to occur. The method also includes executing, by a processor contained in the hard copy output engine, a predetermined protocol at a time based on estimated hard copy output engine usage and estimated lead time for servicing the service event.
In accordance with another aspect of the present invention, an article of manufacture includes a computer usable medium having computer readable code embodied therein. The computer readable code is configured to cause a processor to estimate when a service event for a hard copy output engine is likely to occur and to estimate, from a record of past usage of the hard copy output engine, when peak usage is likely to occur. The computer readable code is also configured to cause the processor to determine when the service event estimate is contemporaneous with the peak usage estimate and to execute a predetermined protocol when determining is indicative of contemporaneous estimates.
In accordance with yet another aspect of the present invention, a computer implemented control system for a hard copy output engine includes memory coupled to the hard copy output engine and configured to store data representing historical usage of the hard copy output engine. The system also includes processing circuitry coupled to the hard copy output engine and to the memory. The processing circuitry is configured to estimate when a service event is likely to occur and to estimate, from the stored historical usage data, when peak usage is likely to occur. The processing circuitry also is configured to determine when the service event estimate is contemporaneous with the peak usage estimate and to execute a predetermined protocol when the processing circuitry configured to determine determines contemporaneous estimates.
Other features and advantages of the invention will become apparent to those of ordinary skill in the art upon review of the following detailed description, claims and drawings.